Russia has reacted strongly to Thailand’s decision to extradite alleged Russian arms merchant Viktor Bout to face trial in the United States, calling the move ‘politicised’. Bout has been held in a Thai prison since his arrest in 2008 by American and Thai agents posing as buyers for Columbian FARC rebels.

A court has now ruled that Bout’s case is criminal, overturning a decision that it was political, so extradition can go ahead.

The 43-year-old former Soviet army officer is wanted on charges in the US that he was conspiring to sell arms. He is alleged to have been a supplier, since the 1990s, of weapons in Africa, South America and the Middle East, through his air transport businesses.

Russian Foreign Minister Sergei Lavrov said: “This verdict is unlawful and we are concerned. The Thai court’s decision is political and is regrettable. We have been giving this Russian citizen assistance all these months, in contact with his lawyers and family. We will keep doing our best to bring him home.”

Bout’s wife has accused Thailand of bowing to US pressure. Washington has hailed the Thai decision, calling the trial an absolute priority. Its indictment says Bout conspired to kill Americans and provided material support to terrorists. Experts say Bout has been useful for Russia’s intelligence apparatus, and Moscow does not want him going on trial in the US.